| Ubaste | platform game | — | Microsoft Windows |
| UBERMOSH | action game | — | Microsoft Windows, Linux |
| UBERMOSH:SANTICIDE | action game | — | Microsoft Windows |
| Ubersoldier II | — | Burut CT | Microsoft Windows |
| Uchū Kaitō Funny Bee | eroge, adventure video game | AliceSoft | Microsoft Windows |
| UEFA Champions League Season 1999/2000 | — | Silicon Dreams Studios | Microsoft Windows |
| UEFA Champions League Season 2001/2002 | sports video game | Silicon Dreams Studios | Microsoft Windows |
| UEFA Euro 2004 | association football video game | EA Vancouver | Microsoft Windows |
| UEFA EURO 2016 / Pro Evolution Soccer 2016 | association football video game | — | — |
| UFC 4 | fighting game, sports video game | EA Vancouver | — |
| UFOTOFU: HEX | casual game | — | Microsoft Windows, macOS, Linux |
| UK Truck Simulator | — | SCS Software | Microsoft Windows |
| Ultima I: The First Age of Darkness | role-playing video game | Richard Garriott | Apple IIGS, DOS, MSX, Commodore 64 |
| Ultima II: The Revenge of the Enchantress | role-playing video game | Richard Garriott | Classic Mac OS, DOS, Atari ST, MSX, Commodore 64 |
| Ultima Online | massively multiplayer online role-playing game | Origin Systems | Microsoft Windows, Linux |
| Ultima Underworld II: Labyrinth of Worlds | role-playing video game | Looking Glass Studios | Microsoft Windows, DOS |
| Ultimate Epic Battle Simulator 2 | casual game, simulation video game, adventure video game, action game, action-adventure game, strategy video game | Brilliant Game Studios | Microsoft Windows |
| Ultimate Mortal Kombat | fighting game | Other Ocean | Nintendo DS |
| Ultimate Mortal Kombat 3 | post-apocalyptic video game, fighting game | Midway Games | Nintendo DS, Super Nintendo Entertainment System, Game Boy, 3DO |
| Ultimate Rivals: The Rink | arcade, sports video game | Bit Fry | macOS |
| Ultimate Spider Hero | — | For Kids | Microsoft Windows, macOS, Linux |
| Ultimate Tic-Tac-Toe | casual game | — | Microsoft Windows |
| Ultimechs | sports video game | Resolution Games | Microsoft Windows |
| Ultra Kaiju Monster Rancher | life simulation game | Koei Tecmo Games | — |
| Ultra Seven | fighting game | Bandai | Super Nintendo Entertainment System |
| Ultra Street Fighter II: The Final Challengers | fighting game | Capcom | — |
| UltraGoodness | adventure video game, action game, action-adventure game | Rasul Mono | Microsoft Windows, Xbox Series X and Series S |
| Ultrakill | boomer shooter, first-person shooter | Arsi Patala | Microsoft Windows |
| Umineko: Golden Fantasia | fighting game | 07th Expansion | Microsoft Windows |
| UNBEATABLE [white label] | adventure video game, action game, action-adventure game | — | Microsoft Windows |
| Unbroken Warrior | — | — | Microsoft Windows, macOS |
| Uncharted Waters Origin | massively multiplayer online role-playing game | — | Microsoft Windows |
| Uncharted: The Lost Legacy | action-adventure game, third-person shooter | Naughty Dog | — |
| UNDEFINED | — | — | Microsoft Windows |
| Under Night In-Birth Exe:Late[cl-r] | fighting game | French-Bread | Microsoft Windows |
| Under The Moon | platform game | — | Microsoft Windows |
| UnderDungeon | dungeon crawl | — | Microsoft Windows, Xbox Series X and Series S |
| Underground Keeper | — | — | Microsoft Windows |
| Underground Life | — | — | Microsoft Windows |
| Underground Sheriff | casual game, adventure video game, action game, action-adventure game, strategy video game | — | Microsoft Windows |
| UnderHero | adventure video game, role-playing video game | — | Microsoft Windows, macOS, Linux |
| Undernauts: Labyrinth of Yomi | role-playing video game | — | Microsoft Windows, Xbox Series X and Series S |
| Underwater | adventure video game, action game, action-adventure game | — | Microsoft Windows |
| Underwater Life | casual game, simulation video game, adventure video game | — | Microsoft Windows |
| Underway | adventure video game, role-playing video game | — | Microsoft Windows |
| Undetected | action game | — | Microsoft Windows |
| Unforgettable Voyage | casual game, adventure video game, strategy video game | — | Microsoft Windows, macOS, Linux |
| Unhack 2 | visual novel | — | Microsoft Windows, macOS, Linux |
| Unheard - Voices of Crime | adventure video game | NExT Studios | Microsoft Windows, macOS |
| Unicorn Dungeon | — | — | Microsoft Windows, Linux |
| Uniseas | simulation video game, strategy video game | Sokpop Collective | Microsoft Windows, macOS |
| Unit 4 | action game | — | Microsoft Windows |
| Universal Soldier | — | The Code Monkeys | Game Boy |
| Unlimited Saga | role-playing video game | Square Enix | — |
| Unlock The King 3 | casual game | — | Microsoft Windows, macOS |
| Unnatural Season Two | adventure video game, role-playing video game | — | Microsoft Windows, macOS, Linux |
| Unreal Golf | — | — | Microsoft Windows |
| Unreal II: The Awakening | first-person shooter | Legend Entertainment | Microsoft Windows |
| Unreal Tournament 2004 | first-person shooter | Q739711 | Microsoft Windows, macOS, Linux |
| Unreal Tournament 3 | first-person shooter | Q739711 | PlayStation 3, Microsoft Windows |
| Unsolved Case | casual game, adventure video game | — | Microsoft Windows, macOS |
| Unsolved Mystery Club: Amelia Earhart | casual game, simulation video game, adventure video game, strategy video game | Freeze Tag | Microsoft Windows |
| Unstable Rock | adventure video game | — | Microsoft Windows |
| Unstrong Legacy | — | Origamihero Games | — |
| Untale: King of Revinia | adventure video game | — | Microsoft Windows, Linux |
| Untamed: Life Of A Cougar | — | — | Microsoft Windows |
| Unterwegs in Dusterburg | role-playing video game | — | Microsoft Windows |
| Until Dawn: Rush of Blood | — | Supermassive Games | — |
| UpGun | casual game, action game | — | Microsoft Windows |
| Uphill: Sierra Nevada Fire Rescue | — | Uphill Games | web browser |
| UpMove | adventure video game, action game, action-adventure game, racing video game | — | Microsoft Windows |
| Urban Basketball | — | — | Microsoft Windows |
| Urban Dead | — | — | web browser |
| Urban Explorer Golf | — | — | Microsoft Windows |
| Urban Mage | casual game, action game | — | Microsoft Windows |
| Urban Strife | strategy video game, role-playing video game | — | Microsoft Windows |
| Urfin Jus and his Wooden Soldiers | adventure video game | — | Microsoft Windows |
| Uridium 2 | — | Andrew Braybrook | — |
| US and THEM | — | — | Microsoft Windows |
| US Spy: Mission in Russia | simulation video game, strategy video game | — | Microsoft Windows, macOS |
| Utawarerumono: Lost Flag | gacha game, visual novel, role-playing video game | Aquaplus | Android |
| Utomah | adventure video game, action game, action-adventure game | — | Microsoft Windows |